题解：P14298 [JOI2023 预选赛 R2] JOI 运动会 / JOI04

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=3e5+20;
int n;
struct node{
    int val,from;
}z[N];
int tot;
bool cmp(node x,node y){
    return x.val<y.val;
}
signed main(){ 
    cin>>n;
    tot=1;
    for(int i=1;i<=4*n;i++){
        cin>>z[i].val;
        z[i].from=tot;
        if(i%n==0) tot++;
    }
    tot=4;
    int lst_1=0,lst_2=0,lst_3=0,lst_4=0;
    int ans=1e9;
    sort(z+1,z+1+4*n,cmp);
    for(int i=1;i<=4*n;i++){
        if(z[i].from==1) lst_1=i;
        if(z[i].from==2) lst_2=i;
        if(z[i].from==3) lst_3=i;
        if(z[i].from==4) lst_4=i;
        if(lst_1&&lst_2&&lst_3&&lst_4) {
            int minn=min(min(lst_1,lst_2),min(lst_3,lst_4));
            ans=min(ans,z[i].val-z[minn].val);
        }
    }
    cout<<ans;
}